Biometrics of the Spotless Starling (Sturnus unicolor Temm.) in West-central Iberian Peninsula
Standard statistical tests and discriminant analysis were used to relate morphological measurements to sex and age in Sturnus unicolor Temm. Adult and first year male birds have longer wings, tarsus and tail than females, these differences being statistically significant. However, differences in total body length and culmen length are only statistically significant in adult birds: males are in average longer than females. Difference in culmen width is not statistically significant between sex in any age group. Nevertheless, it is not completely safe to classify sex and age according to biometrics because the probability of mis-classification remains so high as 25% for all sex-age groups. The most accurate criteria for sexing and aging Spotless Starling are thus, the morphological ones described by earlier authors.